one critical republic who criticized house speaker john boehner over own party fiscal cliff honor says is he resigning. an important man, too. south carolina senator jim demint a key force behind the tea party movement. the founder of the tea party caucus in the senate and who predicted that the healthcare debate would be president obama's water loo. remember that? earlier this week he argued that speaker boehner's proposal tax hikes would destroy jobs. but senator demind says his resignation has nothing to do with the fiscal cliff. it's because he has accepted a job as president of the conservative think tank the heritage foundation. jim demint served three terms as a u.s. congressman from south carolina before voters first elected him to the senate in 2004. mike emanuel is on capitol hill tonight. it's a big resignation,. >> jim demint says is he leaving the senate, shep he is not leaving the fight. in fact, demint might be able to spend more time on issues he is most passionate about at the heritage foundation. he explained his thinking on "special report" a short time ago. >> i thi